Heh.
I'm somewhat relived to see this thread. 2 weekends ago, I fully serviced the hydraulics on my newly-acquired B7100HST. Fully drained oil (3 drain plugs), new filter canister, cleaned strainers. Fold-out maintenance wall chart said 3.6 US gals of fluid. I put in approx 3 1/2 gals...nearly overflowing out the dipstick tube. Well, I figured it would suck some up when everything was turning.
Hooked up the brush-hog for counterweight, raised it with the 3PH, and started moving some gravel around with the FEL...I bumped the brush hog a few times on the ground (NOT very hard). I really wasn't working the tractor very hard, just small scoops and float-smoothing...just FEL ops 101;-).
After about 15 minutes (70*F day), I noticed a shiny wet trail. Stopped the tractor...the rear end was wet from the seat down, but no obvious cracks or pressurized leakage. Ya, I was embarrassed and scared. But I kinda figured the hyd system would have a breather somewhere, likely at the high point of the system. I just didn't know where it was. So I decided to suck out some fluid, to get back down to the dipstick mark. I ended up sucking out 5 PINTS of fluid to get down to the dipstick mark!!! I now assume the 3.6 gal capacity is for a freshly assembled, dry hyd system. That HST must hold a lotta fluid.
Anyways, no time to play, er, work, with the tractor since then, but gonna mess with it this weekend. Sometimes I just gotta walk away for a bit, when things go sideways with things I'm not very familiar with.
Sorry for the long-winded story. Just thought I'd share.